uhd: set and shadow settings through interface
uhd: set and shadow settings through interface

Shadow all gains and frequencies, which minimizes device access.
This allows the transceiver to variably control the device
settings.

Signed-off-by: Thomas Tsou <ttsou@vt.edu>

git-svn-id: 504cad4147f1e500be0a169b9f46375eaf875953@2640 19bc5d8c-e614-43d4-8b26-e1612bc8e597

osmocom/osmo-trx,pothosware/osmo-trx,pothosware/osmo-trx,telenoobie/osmo-trx,osmocom/osmo-trx,kkroo/osmo-trx,ttsou/osmo-trx,osmocom/osmo-trx,ttsou/osmo-trx,kkroo/osmo-trx,kkroo/osmo-trx,telenoobie/osmo-trx,pothosware/osmo-trx,pothosware/osmo-trx,kkroo/osmo-trx,telenoobie/osmo-trx,telenoobie/osmo-trx,ttsou/osmo-trx,ttsou/osmo-trx,osmocom/osmo-trx